Reinforced plastics industry

Exposure to styrene is the main occupational hygiene problem in reinforced plastics industry, where it is used as a crosslinking agent and solvent in unsaturated polyester resins. In addition, workers are exposed to acetone which is used as a clean-up solvent. Other solvents, such as methylene chloride, toluene, xylene, heptane (TLV 400 ppm, the Finnish OEL 300 ppm), methylcyclohexane (TLV and the Finnish OEL 400 ppm), and butyl acetate (TLV and the Finnish OEL 150 ppm) may also be used. Styrene is neurotoxic. Styrene is also a suspected carcinogen because it is metabolized via styrene-7,8-oxide. The TLV and the Finnish OEL of styrene is 20 ppm. Urinary mandelic acid concentration is the most common biological monitoring method for styrene. The ACGIH BEI is 800 mg/g creatinine and the FIOH BEI 3.2 mmol/1. 

Open mold methods (hand lay-up and spray-up methods) are most commonly used. In addition, the products often have large surface areas and large styrene vapor emissions take place. The emission depends on the type of resin used. While the mean evaporation loss of styrene was 11.6% for conventional resins, it was only 4.4% for the low styrene emission (LSE) resins containing volatilization inhibitors.  

The mean urinary mandelic acid concenfration was about 5 mmol/l in the late 1970 s in Finland. The level was reduced to about 4 mmoI/1 in mid-1980 s and to 35 mmol/l in late 1980 s. However, the maximum levels remained above 30 mmol/l flnoughoutthe whole period.  

Recent studies have indicated that sophisticated ventilation arrangements are needed to reduce the concentration of styrene below 20 ppm. In hand lay-up work, this is possible by the use of a mobile supply ventilation and exhaust ventilation. In the spray-up work, concentrations below 20 ppm can be achieved by using a booth provided with mobile curtains to reduce the open face area and by maintaining a control velocity of 0.35 m/s.  

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Occupational and environmental exposure to chemicals can take place both indoors and outdoors. Occupational exposure is caused by the chemicals that are used and produced indoors in industrial plants, whereas nonoccupa-tional (and occupational nonindustrial) indoor exposure is mainly caused by products. Toluene in printing plants and styrene in the reinforced plastic industry are typical examples of the two types of industrial occupational exposures. Products containing styrene polymers may release the styrene monomer into indoor air in the nonindustrial environment for a long time. Formaldehyde is another typical indoor pollutant. The source of formaldehyde is the resins used in the production process. During accidents, occupational and environmental exposures may occur simultaneously. Years ago, dioxin was formed as a byproduct of production of phenoxy acid herbicides. An explosion in a factory in... 

Aqueous Epoxy Resins for Electrical Reinforced Plastics Industry... 

The electrical reinforced plastics industry is undergoing changes as the requirements of printed circuit boards become more complex. This complexity is compounded by the requirements that the processes be more environmentally acceptable. EPA acceptable resins will ultimately be required of the resin producers. 

A new water based epoxy resin system has been developed for the electrical reinforced plastics industry. 

Composite Institute An organization that represents the reinforced plastics industry and is part of the Society of the Plastics Industry. In the late 1940s it started as the Reinforced Plastics Division of SPI. See composite reinforced plastic. 

National Association of the Composites and Reinforced Plastics Industries)... 

As the reinforced plastic industry worldwide continues to grow and expand its capabilities material wise, process wise, design wise, and product wise, so does the literature. This Third Edition of the Reinforced Plastics book and the Reinforced Plastics magazine published by Elsevier Advanced Technology provides important information. 

Source Reprinted from Corrq>osites A Profile of the Worldwide Reinforced Plastics Industry, Markets Suppliers from 2005,3rd edition, T.F. Starr, Copyright 1999, with permission from Elsevier. 

M Skrifwars, H Manninen and K Strang, Recycling of production waste from the fibre-reinforced plastics industry , Rivestimenti Materiali Compositi 1997 (18) 36-40. 

A. Saamanen, Methods to Control Styrene Exposirre in the Reinforced Plastics Industry, Publications of the Technical Research Centre in Finland No. 354, Espoo, 1998. 

G.K. Lemasters, An epidemiological study ofpregnant workers in the reinforced plastics industry assessing outcomes associated with live births. University of Cincinnati, Cincinnati, 1983. 

Various fabrications used in the reinforced plastics industry are discussed below ... 

Kolstad HA, Ebbehpj N, Bonde JP, Lynge E, Albin M. Health effects following occupational styrene exposure in the reinforced plastics industry. Ugeskr Laeger 2012 174 (5) 267-270. 

Laminate la-m3- nat (1665) (1, n). A product made by bonding together two or more layers of material or materials. The term most usually applies to preformed layers joined by adhesives or by heat and pressure. However, some authors apply the term to composites of plastic films, with other films, foils, and papers, even though they have been made by spread coating or by extrusion coating. In the reinforced-plastics industry, the term refers mainly to superimposed layers of resin-impregnated or resin-coated fabrics or fibrous reinforcements that have been... 

Tarvainen K, Jolanki R, Forsman-Gronholm L, et al. (1993) Exposure, skin protection and occupational skin disease in the glass-fibre-reinforced plastics industry. Contact Dermatitis 29 119-127... 

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